check the environment variable path
Control Panel>Advanced>Environment Variables. Make sure "%SystemRoot%\System32\" is in the path.
or just go to the command prompt and type "path" and check if system32 is in the path. if not then add the path its like this type at the prompt

path=%path%;"%SystemRoot%\winnt\System32\"

[edit] ok just do one thing type this at the prompt
path=%path%;%SystemRoot%\winnt\System32\"
then check the netstat or ping command and tell what happens